I'm loosing so many followers

I have an art page.
it has grown very fast, very quick. I've 20k followers. I've always been so active with stories and posts (I've been posting one post every 3-2 days, sometimes 1), and I've never complained. each story had 2k visualization, and everything was fine.
two months ago, all of the sudden, I started to lose followers. I don't mean a little bit of followers every day, but almost 100 followers every day, without any reason! I didn't change anything, then I wake up and boom, surprise. my self esteem started to get lower everyday. now, after 2 month, I've lost more than 500 followers, and each story get only 700-800 visualization. I'd like to know why.. I've tried to post less, to post more, to be more active, but nothing changed. is instagram deleting accounts, the algorithm or just.. me? I don't know if instagram is deleting accounts again, but I'd like to know.
thank you!

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